Glass fiber reinforced polycarbonate molding compositions

ABSTRACT

The invention relates to glass fiber reinforced polycarbonate compositions and molding compositions of the present inventor and distinguished by high rigidity, high flowability, high processing stability, good chemical resistance and good aging resistance vis-à-vis the effects of light and heat compared with the prior art. The present invention also relates to the use of the compositions for the production of shaped articles and to shaped articles comprising the compositions according to the invention.

CROSS REFERENCE TO RELATED APPLICATION

This application claims priority from DE 102007038438 filed Aug. 16,2007, the content of which is incorporated herein by reference in itsentirety.

BACKGROUND OF THE INVENTION

The invention relates to glass fiber reinforced polycarbonatecompositions and molding compositions, which are distinguished by highrigidity, high flowability, high processing stability, good chemicalresistance and good aging resistance vis-à-vis the effects of light andheat compared with the prior art.

1. Description of Related Art

Compositions containing polycarbonate and rubber-modified styrenepolymers, such as e.g. ABS (acrylonitrile-butadiene-styrene polymers),are known for their balance of excellent mechanical properties and goodmelt flowability. They are used in many different areas of application,for example, in car construction, in the building sector and in housingsfor office equipment and domestic appliances.

A low coefficient of thermal expansion and good dimensional stability,as well as shape stability and high rigidity, are generally needed toproduce moulded parts with a large surface area. These properties can beachieved by the addition of fillers or reinforcing materials. Highmoduli of elasticity can be obtained particularly by adding fibrousreinforcing materials. However, the addition of the fillers orreinforcing materials generally has a disadvantageous effect on thetoughness and particularly on the flow properties of the polymer melts,i.e. the processing characteristics. As a result, increased processingtemperatures are usually required, which entails a further reduction inmaterial toughness. The practicable degrees of filling with reinforcingmaterial, and thus the material rigidities that can be achieved are, ineffect, limited by these parameters, and moulded parts with largesurface areas and very thin walls are often impossible to produce withthose polycarbonate compositions that correspond to the prior artdescribed below. For these areas of application there is a demand forsuch polycarbonate compositions to be produced with improved flowabilityand a higher modulus of elasticity, and with a toughness which is goodover a broad processing window and stable vis-à-vis heat aging. Sincemoulded parts produced from compositions of this type are often paintedand, in the context of the post-treatment needed in connection withthis, generally come into contact with chemicals, such as e.g. paintsolvents, there is a further demand for adequate chemical resistance.For this reason, the use of low molecular weight polycarbonates toimprove the polymer melt flowability is out of the question, since theseusually lead to a negative effect on stress cracking resistance.

Rubber-modified vinyl copolymers containing glass fiber reinforcedpolycarbonate compositions are known from the prior art.

WO-A 00/39210 discloses polycarbonate compositions containingpolycarbonate, styrene resin, phosphoric ester and reinforcing agents(e.g. glass fibers), as well as optionally a graft polymer based on asilicone-acrylate composite rubber with a vinyl monomer-based graftshell, which are distinguished by improved hydrolysis resistance, goodflame resistance and by improved mechanical properties. The styreneresins employed contain a rubber-based graft polymer. No glass fibersizes are disclosed.

EP-A 1 240 250 discloses polycarbonate compositions containing 10-93 wt.% polycarbonate, 3-50 wt. % rubber elastic-based graft polymer, 3- 50wt. % thermoplastic copolymer and 1-20 wt. % of a mixture of particulatemineral and fibrous fillers, which are distinguished by reduced thermalexpansion, good toughness, good dimensional stability and highflowability together with improved surface quality in the region of thegate.

EP-A 0 624 621 discloses polycarbonate compositions containing 10-80 wt.% polycarbonate, 10-80 wt. % rubber-modified graft polymer and 5-50 wt.% glass fibers with a coating containing polyolefin wax, which aredistinguished by improved toughness and ductility.

EP-A 0 345 652 discloses polycarbonate compositions containing 10-75 wt.% polycarbonate, 10-50 wt. % rubber-based graft copolymer, up to 50 wt.% styrene copolymer, 0.5-50 wt. % terpolymer containing tert-butyl(meth)acrylate and 5 to 50 wt. % reinforcing agents (e.g. glass fibers),which are distinguished by high strength, good toughness and by lowyellowing. The glass fibers used in this cited application are generallyprovided with a size and an adhesion promoter, but the composition ofthe size is not disclosed here.

The prior art documents cited above do not, however, disclose anycompositions that contain polycarbonate, rubber-free vinyl copolymers(e.g. styrene-acrylonitrile copolymers) and no rubber-containing graftpolymer or only very small quantities thereof (i.e. up to 2 wt. %).

Disadvantages of the compositions described in the prior art, whichcontain rubber-modified graft polymers in quantities of more than 2 wt.%, are too low a melt flowability and inadequate aging resistance.

Compositions containing polycarbonate, glass fibers and rubber-freevinyl copolymer, which contain no rubber-modified vinyl copolymers oronly very small quantities thereof, are also known from the prior art.

WO-A 84/04317 discloses polycarbonate compositions containingpolycarbonate, styrene resin, unsized glass fibers and a hydrogenpolysiloxane, which are distinguished by high impact resistance and ahigh modulus.

EP-A 0 647 679 discloses polycarbonate compositions containing specialcopolycarbonates with bisphenol and resorcinol monomer units,rubber-containing copolymer and/or copolymer of vinyl aromatic andcyanated vinyl monomer components as well as inorganic filler (e.g.glass fibers), which are distinguished by good flowability, high impactresistance and good surface quality. No glass fiber sizes are disclosed.

EP-A 1 038 920 discloses polycarbonate compositions substantiallyconsisting of a special aromatic polycarbonate produced by meltpolymerization, a styrene-based resin (e.g. a styrene-acrylonitrilecopolymer with a styrene content of at least 20%, preferably at least30%), a reinforcing fibrous filler and optionally an elastomericpolymer, which are distinguished by improved moist heat resistance andimproved toughness. It is disclosed that the glass fibers used may becoated with a size made of polymers (such as e.g. epoxy resin, urethaneresin, acrylic resin, nylon resin etc.). In the examples, onlycompositions containing polyurethane-sized glass fibers are disclosed.

WO-A 2006/040087 discloses polycarbonate compositions containingpolycarbonate, a terpolymer of styrene, acrylonitrile and maleicanhydride, and long glass fibers, which are distinguished by acombination of improved tensile strength, modulus of elasticity andimpact resistance. In addition, these compositions preferably contain atleast one polymer selected from the group of the rubber-containing graftpolymers and rubber-free copolymers. It is disclosed that the long glassfibers may be surface-modified with a size, without any information onthe chemistry of the size being disclosed.

Although the glass fiber reinforced polycarbonate compositions based onrubber-free styrene resins disclosed in the prior art do generallyexhibit good melt flowability and aging resistance, they are, however,distinguished by inadequate toughness for certain areas of application,particularly at higher processing temperatures, and by unsatisfactorychemical resistance and rigidity.

SUMMARY OF THE INVENTION

This invention was therefore based, inter alia, on an object ofproviding free-flowing polycarbonate compositions which are resistant toaging vis-à-vis the effects of heat and light, with improved processingstability (i.e. stable toughness even at higher processingtemperatures), improved rigidity and improved chemical resistance.

Surprisingly, it has been found that this object can be achieved byproviding a composition comprising:

-   -   A) 10 to 85 parts by weight, preferably 30 to 80 parts by        weight, especially 40 to 70 parts by weight polycarbonate,        polyester carbonate or a mixture thereof,    -   B) 10 to 50 parts by weight, preferably 15 to 40 parts by        weight, especially 20 to 35 parts by weight rubber-free vinyl        copolymer,    -   C) 5 to 50 parts by weight, preferably 7 to 35 parts by weight,        especially 8 to 25 parts by weight of a sized glass fiber,        wherein the size comprises an epoxy polymer,    -   D) 0 to 2 parts by weight, preferably 0 to 1 parts by weight,        particularly preferably 0 parts by weight of rubber-modified        graft polymers (in other words, the composition is preferably        free of rubber-modified graft polymers), and    -   E) 0 to 10 parts by weight, preferably 0.01 to 5 parts by        weight, especially 0.1 to 3 parts by weight of commercial        polymer additives,

the composition further being free from rubber-modified polymers whichdiffer from component D).

The sum of the components A+B+C+D+E is standardized to 100 parts byweight.

Additional objects, features and advantages of the invention will be setforth in the description which follows, and in part, will be obviousfrom the description, or may be learned by practice of the invention.The objects, features and advantages of the invention may be realizedand obtained by means of the instrumentalities and combinationparticularly pointed out in the appended claims.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT Component A

Aromatic polycarbonates and/or aromatic polyester carbonates accordingto component A which are suitable according to the invention are knownfor example, from the literature and/or can be produced by processesknown from the literature (for the production of aromaticpolycarbonates, cf. for example Schnell, “Chemistry and Physics ofPolycarbonates”, Interscience Publishers, 1964, and DE-AS 1 495 626,DE-A 2 232 877, DE-A 2 703 376, DE-A 2 714 544, DE-A 3 000 610, DE-A 3832 396; for the production of aromatic polyester carbonates, e.g. DE-A3 077 934), the contents of which is incorporated herein by reference intheir entireties.

The production of aromatic polycarbonates can take place e.g. bytransesterification of diphenols with carbonic acid halides, preferablyphosgene, and/or with aromatic dicarboxylic acid dihalides, preferablybenzenedicarboxylic acid dihalides, by the interfacial polycondensationprocess, optionally using chain terminators, for example monophenols,and optionally using branching agents which are trifunctional or morethan trifunctional, for example triphenols or tetraphenols. Productionvia a melt polymerization process by reaction of diphenols with, forexample, diphenyl carbonate is also possible.

Diphenols for the production of the aromatic polycarbonates and/oraromatic polyester carbonates are preferably those of the formula (I)

wherein

-   -   A is a single bond, C₁ to C₅ alkylene, C₂ to C₅ alkylidene, C₅        to C₆ cycloalkylidene, —O—, —SO—, —CO—, —S—, —SO₂—, C₆ to C₁₂        arylene, on to which further aromatic rings optionally        containing heteroatoms may be condensed, or a radical of the        formula (II) or (III)

-   -   B in each case is C₁ to C₁₂ alkyl, preferably methyl, or        halogen, preferably chlorine and/or bromine,    -   x in each case independently of one another, is 0, 1 or 2,    -   p is 1 or 0 and    -   R⁵ and R⁶ are selected individually for each X¹ and        independently of one another denote hydrogen or C₁ to C₆ alkyl,        preferably hydrogen, methyl or ethyl,    -   X¹ denotes carbon and    -   m denotes an integer from 4 to 7, preferably 4 or 5, with the        proviso that on at least one atom X¹, R⁵ and R⁶ are        simultaneously alkyl.

Preferred diphenols include hydroquinone, resorcinol,dihydroxydiphenols, bis(hydroxyphenyl)-C₁-C₅-alkanes,bis(hydroxyphenyl)-C₅-C₆-cycloalkanes, bis(hydroxyphenyl) ethers,bis(hydroxyphenyl) sulfoxides, bis(hydroxyphenyl) ketones,bis(hydroxyphenyl) sulfones and α,α-bis(hydroxyphenyl)diisopropylbenzenes and ring-brominated and/or ring-chlorinatedderivatives thereof.

Particularly preferred diphenols are 4,4′ dihydroxydiphenyl, bisphenolA, 2,4-bis(4-hydroxyphenyl)-2-methylbutane,1,1-bis(4-hydroxyphenyl)-cyclohexane,1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane,4,4′-dihydroxydiphenyl sulfide, 4,4′-dihydroxydiphenyl sulfone and di-and tetrabrominated or chlorinated derivatives thereof, such as, forexample, 2,2-bis(3-chloro-4-hydroxyphenyl)propane,2,2-bis(3,5-dichloro-4-hydroxyphenyl)propane or2,2-bis(3,5-dibromo-4-hydroxyphenyl)propane.2,2-Bis(4-hydroxyphenyl)propane (bisphenol A) is especially preferred.

The diphenols may be employed individually or as any desired mixtures.The diphenols are known from the literature or obtainable by processesknown from the literature.

Chain terminators which are suitable for the production of thethermoplastic, aromatic polycarbonates are, for example, phenol,p-chlorophenol, p-tert-butylphenol or 2,4,6-tribromophenol, and alsolong-chain alkylphenols, such as 4-[2-(2,4,4-trimethylpentyl)]phenol,4-(1,3-tetramethylbutyl)phenol according to DE-A 2 842 005 ormonoalkylphenol or dialkylphenols having a total of 8 to 20 carbon atomsin the alkyl substituents, such as 3,5-di-tert.-butylphenol,p-iso-octylphenol, p-tert.-octylphenol, p-dodecylphenol and2-(3,5-dimethylheptyl)phenol and 4-(3,5-dimethylheptyl)phenol. Theamount of chain terminators to be employed is generally between 0.5 mole% and 10 mole %, based on the sum of the moles of the particulardiphenols employed.

The thermoplastic, aromatic polycarbonates may be branched in a knownmanner, and preferably by incorporation of 0.05 to 2.0 mole %, based onthe sum of the diphenols employed, of compounds which are trifunctionalor more than trifunctional, for example those having three and morephenolic groups.

Both homopolycarbonates and copolycarbonates are suitable. It is alsopossible for 1 to 25 wt. %, preferably 2.5 to 25 wt. %, based on thetotal amount of diphenols to be employed, of polydiorganosiloxaneshaving hydroxyaryloxy end groups to be employed for the production ofcopolycarbonates according to the invention according to component A.These are known (U.S. Pat. No. 3,419,634) and can be produced byprocesses known from the literature. The preparation of copolycarbonatescontaining polydiorganosiloxanes is described in DE-A 3 334 782.

Preferred polycarbonates are, in addition to the bisphenol Ahomopolycarbonates, the copolycarbonates of bisphenol A with up to 15mole %, based on the sum of the moles of diphenols, of other diphenolsmentioned as preferred or particularly preferred, in particular2,2-bis(3,5-dibromo-4-hydroxyphenyl)propane.

Aromatic dicarboxylic acid dihalides for the production of aromaticpolyester carbonates are preferably the diacid dichlorides ofisophthalic acid, terephthalic acid, diphenyl ether-4,4′-dicarboxylicacid and of naphthalene-2,6-dicarboxylic acid. Mixtures of the diaciddichlorides of isophthalic acid and of terephthalic acid in a ratio ofbetween 1:20 and 20:1 are particularly preferred.

A carbonic acid halide, preferably phosgene, is additionally used as abifunctional acid derivative in the production of polyester carbonates.

Possible chain terminators for the preparation of the aromatic polyestercarbonates are, in addition to the monophenols already mentioned, alsochlorocarbonates thereof as well as the acid chlorides of aromaticmonocarboxylic acids, which may optionally be substituted by C₁ to C₂₂alkyl groups or by halogen atoms, as well as aliphatic C₂ to C₂₂monocarboxylic acid chlorides.

The quantity of chain terminators is in each case 0.1 to 10 mole %,based on the moles of diphenol in the case of the phenolic chainterminators and on the moles of dicarboxylic acid dichloride in the caseof monocarboxylic acid chloride chain terminators.

The aromatic polyester carbonates may also contain incorporated aromatichydroxycarboxylic acids.

The aromatic polyester carbonates may be either linear or branched in aknown manner (in this context see DE-A 2 940 024 and DE-A 3 007 934,incorporated herein by reference in their entireties).

Branching agents which may be used include, for example, acyl chlorideswhich are trifunctional or more than trifunctional, such as trimesicacid trichloride, cyanuric acid trichloride,3,3′,4,4′-benzophenonetetracarboxylic acid tetrachloride,1,4,5,8-naphthalenetetracarboxylic acid tetrachloride or pyromelliticacid tetrachloride, in quantities of from 0.01 to 1.0 mole % (based onthe dicarboxylic acid dichlorides employed), or phenols which aretrifunctional or more than trifunctional, such as phloroglucinol,4,6-dimethyl-2,4,6-tri-(4-hydroxyphenyl)hept-2-ene,4,6-dimethyl-2,4,6-tri-(4-hydroxyphenyl)heptane,1,3,5-tri-(4-hydroxyphenyl)benzene, 1,1,1-tri-(4-hydroxyphenyl)ethane,tri-(4-hydroxyphenyl)phenylmethane,2,2-bis[4,4-bis(4-hydroxyphenyl)cyclohexyl]propane,2,4-bis(4-hydroxyphenylisopropyl)phenol, tetra-(4-hydroxyphenyl)methane,2,6-bis(2-hydroxy-5-methylbenzyl)-4-methyl-phenol,2-(4-hydroxyphenyl)-2-(2,4-dihydroxyphenyl)propane,tetra-(4-[4-hydroxyphenylisopropyl]phenoxy)methane and1,4-bis[4,4′-dihydroxytriphenyl)methyl]-benzene, in amounts of from 0.01to 1.0 mole %, based on the diphenols employed. Phenolic branchingagents may be initially introduced into the reaction vessel with thediphenols, and acid chloride branching agents may be introduced togetherwith the acid dichlorides.

The proportion of carbonate structural units in the thermoplastic,aromatic polyester carbonates may be varied as desired. Preferably, thecontent of carbonate groups is up to 100 mole %, especially up to 80mole %, particularly preferably up to 50 mole %, based on the sum ofester groups and carbonate groups. Both the ester and the carbonatecontent of the aromatic polyester carbonates may be present in thepolycondensate in the form of blocks or in random distribution.

In a preferred embodiment, the component A has a weight-averagemolecular weight Mw (determined by GPC, light scattering orsedimentation) of 23 000 g/mole to 40 000 g/mole, preferably of 24 000g/mole to 35 000 g/mole, especially of 25 000 to 32 000 g/mole.

Component B

In a preferred embodiment, component B is a rubber-free vinyl copolymerof

-   -   B.1 70 to 80 wt. %, preferably 72 to 78 wt. %, especially 75 to        78 wt. % (based in each case on component B), of at least one        monomer selected from the group of the vinyl aromatics (such as,        for example, styrene and α-methylstyrene) or ring-substituted        vinyl aromatics (such as, for example, p-methylstyrene and        p-chlorostyrene) and    -   B.2 20 to 30 wt. %, preferably 22 to 28 wt. %, especially 22 to        25 wt. % (based in each case on component B), of at least one        monomer selected from the group of the vinyl cyanides (such as,        for example, unsaturated nitriles, such as acrylonitrile and        methacrylonitrile), (meth)acrylic acid (C₁-C₈) alkyl esters        (such as, for example, methyl methacrylate, n-butyl acrylate and        tert.-butyl acrylate), unsaturated carboxylic acids and        derivatives of unsaturated carboxylic acids (for example maleic        anhydride and N-phenylmaleimide).

The copolymers B are resinous, thermoplastic and rubber-free.Particularly preferably, component B is a rubber-free copolymer ofstyrene (B.1) and acrylonitrile (B.2).

Copolymers of this type are known and can be produced by free-radicalpolymerization, especially by emulsion, suspension, solution or bulkpolymerization.

The (co)polymers preferably possess average molecular weights (M_(w))(weight average, determined by GPC, light scattering or sedimentation)between 15 000 and 250 000 g/mole, particularly between 50 000 and 200000 g/mole, especially between 80 000 and 160 000 g/mole.

Component C

In a preferred embodiment, component C is a sized glass fiber with

-   -   C. 1 a glass fiber selected from at least one component from the        group comprising and advantageously consisting of continuous        strands (rovings), long glass fibers and chopped glass strands,    -   C.2 a size containing an epoxy polymer (in other words, the        “size” fills pores in the glass fiber or provides a covering or        glaze), and    -   C.3 optionally an adhesion promoter.

Size C.2 and adhesion promoter C.3 are preferably employed in componentC in an amount such that the carbon content measured in component C is0.1 to 1 wt. %, preferably 0.2 to 0.8 wt. %, particularly preferably 0.3to 0.7 wt. %.

The glass fibers according to component C.1 are preferably made from E-,A- or C-glass. The diameter of the glass fibers is preferably 5 to 25μm, particularly preferably 6 to 20 μm, most preferably 7 to 15 μm. Thelong glass fibers preferably have a length of 5 to 50 mm, particularlypreferably 5 to 30 mm, most preferably 7 to 25 mm. Long glass fibers aredescribed e.g. in WO-A 2006/040087, the content of which is incorporatedherein by reference. At least 70 wt. % of the glass fibers in thechopped glass strands preferably have a length of at least about 60 μm.

The size C.2 preferably comprises or consists of

-   -   C.2.1 50 to 100 wt. %, preferably 70 to 100 wt. %, particularly        preferably 80 to 100 wt. % (based on C.2 in each case) epoxy        polymer and    -   C.2.2 0 to 50 wt. %, preferably 0 to 30 wt. %, particularly        preferably 0 to 20 wt. % (based on C.2 in each case) of one or        more other polymers.

Most preferably, in one embodiment the size C.2 consists exclusively ofepoxy polymer C.2.1 (i.e. the size C.2 is free from other polymersaccording to component C.2.2).

The epoxy polymer according to C.2.1 can be an epoxy resin, an epoxyresin ester or an epoxy resin polyurethane, for example.

In a preferred embodiment, the epoxy polymer according to componentC.2.1 is an epoxy resin comprising:

C.2.1.1 epichlorohydrin and

C.2.1.2 a preferably aromatic alcohol, which has at least two hydroxylgroups.

Component C.2.1.2 is preferably a phenolic resin, for example a novolak,or a compound of formula (I). Component C.2.1.2 is particularlypreferably bisphenol A.

Component C.2.2 is preferably at least one polymer selected from thegroup consisting of polyurethanes, polyolefins, acrylate-containingpolymers, styrene-containing polymers and polyamides.

Component C.3 is preferably a silane. In a preferred embodiment, thesilane possesses a functional group selected from the group of the aminogroup, epoxy group, carboxylic acid group, vinyl group and mercaptogroup for binding to the polymer of the size, as well as one to three,preferably three alkoxy groups for binding to the glass fiber. Forexample and preferably, at least one silane selected from the groupconsisting of vinyltrichlorosilane, vinyltriethoxysilane,vinyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane,β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane,γ-glycidoxypropyltrimethoxysilane,N-β-(aminoethyl)-γ-aminopropyltrimethoxysilane,γ-aminopropyltriethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane,γ-mercaptopropyltrimethoxysilane and γ-chloropropyltrimethoxysilane isused as component C.3. Sized glass fibers which contain the componentC.3 typically exhibit better adhesion of the size to the glass fiber.

Component D

Component D comprises one or more graft polymers of

-   -   D.1 5 to 70 wt. %, preferably 10 to 60 wt. %, especially 20 to        50 wt. % of at least one vinyl monomer on    -   D.2 30 to 95 wt. %, preferably 40 to 90 wt. %, especially 50 to        80 wt. % of one or more backbones with glass transition        temperatures of <10° C., preferably <0° C., particularly        preferably <−20° C.

Monomers D.1 are preferably mixtures of

-   -   D.1.1 50 to 99 parts by weight vinyl aromatics and/or        ring-substituted vinyl aromatics (such as styrene,        α-methylstyrene, p-methylstyrene, p-chlorostyrene) and/or        (C₁-C₈) alkyl methacrylates, such as methyl methacrylate, ethyl        methacrylate, and    -   D.1.2 1 to 40 parts by weight of vinyl cyanides (unsaturated        nitriles such as acrylonitrile and methacrylonitrile) and/or        (C₁-C₈) alkyl (meth)acrylates, such as methyl methacrylate,        n-butyl acrylate, t-butyl acrylate, and/or derivatives (such as        anhydrides and imides) of unsaturated carboxylic acids, for        example maleic anhydride and N-phenylmaleimide.

Preferred monomers D.1.1 are selected from at least one of the monomersstyrene, α-methylstyrene and methyl methacrylate; preferred monomersD.1.2 are selected from at least one of the monomers acrylonitrile,maleic anhydride and methyl methacrylate. Particularly preferred monomercombinations are D.1.1 styrene and D.1.2 acrylonitrile or D.1.1 andD.1.2 methyl methacrylate.

The backbones D.2 suitable for the graft polymers D are, in a preferredembodiment, saturated, i.e. substantially free from double bonds. D.2 isparticularly preferably at least one rubber selected from the groupconsisting of acrylate rubbers, silicone rubbers and silicone-acrylatecomposite rubbers. Most preferably, D.2 is at least one rubber selectedfrom the group consisting of silicone rubbers and silicone-acrylatecomposite rubbers.

Suitable acrylate rubbers according to D.2 include preferably polymersof alkyl acrylates, optionally with up to 40 wt. %, based on D.2, ofother polymerisable, ethylenically unsaturated monomers. The preferredpolymerisable acrylates include C₁ to C₈ alkyl esters, for examplemethyl, ethyl, butyl, n-octyl and 2-ethylhexyl esters; haloalkyl esters,preferably halo-C₁-C₈-alkyl esters, such as chloroethyl acrylate, aswell as mixtures of these monomers.

For crosslinking purposes, monomers with more than one polymerizabledouble bond can be copolymerized. Preferred examples of crosslinkingmonomers include esters of unsaturated monocarboxylic acids with 3 to 8C atoms and unsaturated monohydric alcohols with 3 to 12 C atoms, orsaturated polyols with 2 to 4 OH groups and 2 to 20 C atoms, such asethylene glycol dimethacrylate, allyl methacrylate; polyunsaturatedheterocyclic compounds, such as trivinyl and triallyl cyanurate;polyfunctional vinyl compounds, such as di- and trivinyl benzenes; butalso triallyl phosphate and diallyl phthalate. Preferred crosslinkingmonomers are allyl methacrylate, ethylene glycol dimethacrylate, diallylphthalate and heterocyclic compounds having at least three ethylenicallyunsaturated groups. Particularly preferred crosslinking monomers are thecyclic monomers triallyl cyanurate, triallyl isocyanurate,triacryloylhexahydro-s-triazine, triallyl benzenes. The quantity of thecrosslinked monomers is preferably 0.02 to 5, especially 0.05 to 2 wt.%, based on the backbone D.2. In the case of cyclic crosslinkingmonomers with at least three ethylenically unsaturated groups, it isgenerally advantageous to limit the quantity to less than 1 wt. % of thebackbone D.2.

Preferred “other” polymerizable, ethylenically unsaturated monomerswhich may optionally be used in addition to the acrylates for theproduction of the backbone D.2 are e.g. acrylonitrile, styrene,α-methylstyrene, acrylamides, vinyl-C₁-C₆-alkyl ethers and methylmethacrylate.

Other suitable backbones according to D.2 include silicone rubbers withgraft-active points, as described in DE-OS 3 704 657, DE-OS 3 704 655,DE-OS 3 631 540 and DE-OS 3 631 539.

The graft copolymers D can be produced for example by free-radicalpolymerization, preferably by emulsion polymerization.

The backbone D.2 generally has an average particle size (d₅₀ value) of0.05 to 1 μm, preferably 0.07 to 0.5 μm, particularly preferably 0.1 to0.4 μm. The average particle size d₅₀ is the diameter having 50 wt. % ofthe particles lying above it and 50 wt. % below it. It can be determinedby means of ultracentrifuge measurement (W. Scholtan, H. Lange, Kolloid,Z. und Z. Polymere 250 (1972), 782-1796).

The gel content of the backbone D.2 in graft polymers produced byemulsion polymerization is preferably at least 30 wt. %, particularlypreferably at least 40 wt. %, especially at least 50 wt. % (measured intoluene). The gel content is determined at 25° C. in a suitable solventas the portion that is insoluble in these solvents (M. Hoffmann, H.Krömer, R. Kuhn, Polymeranalytik I and II, Georg Thieme-Verlag,Stuttgart 1977).

Since it is known that, during the graft reaction, the graft monomersare not necessarily grafted on to the backbone completely, graftpolymers D according to the invention also include those productsobtainable by (co)polymerization of the graft monomers in the presenceof the backbone and jointly formed during the work-up. These productscan therefore also contain free (co)polymer of the graft monomers, i.e.they are not chemically bonded to the rubber.

E) Other Components

The composition may contain other optional additives as component E,with polymer additives such as flame retardants (e.g. organic phosphorusor halogen compounds, especially bisphenol A-based oligophosphate),anti-drip agents (e.g. compounds of the classes of substances of thefluorinated polyolefins, the silicones and aramid fibers), lubricantsand mould release agents, e.g. pentaerythritol tetrastearate, nucleatingagents, antistatic agents, stabilisers, fillers and reinforcingmaterials other than component C (e.g. carbon fibers, talc, mica,kaolin, CaCO₃), as well as dyes and pigments (e.g. titanium dioxide oriron oxide), being particularly suitable.

Production of the Molding Compositions and Shaped Articles

The thermoplastic molding compositions according to the invention can beproduced, for example, by mixing the respective components in a knownmanner and melt-compounding and melt-extruding them at temperatures of200° C. to 320° C., preferably at 240 to 300° C., in conventionalequipment such as internal mixers, extruders and twin screw extruders.

The mixing of the individual components can take place in a knownmanner, either successively or simultaneously, and either at about 20°C. (room temperature) or at a higher temperature.

In a preferred embodiment, the production of the compositions accordingto the invention takes place in a twin screw extruder, the components A,B, D and E first being melted and mixed and the glass fibers C thenbeing introduced into the melt mixture via a subsidiary extruder anddispersed therein.

The invention thus also provides a process for the production of thecompositions according to the invention.

The molding compositions according to the invention can be used for theproduction of shaped articles of all kinds. These can be produced, forexample, by injection molding, extrusion and blow molding processes.Another form of processing is the production of shaped articles bythermoforming from previously produced sheets or films.

Examples of these shaped articles are films, profiles, all kinds ofhousing parts, e.g. for domestic appliances such as juice presses,coffee machines, mixers; for office equipment such as monitors, flatscreens, notebooks, printers, copiers; sheets, pipes, electricalinstallation ducts, windows, doors and other profiles for theconstruction sector (interior finishing and exterior applications) aswell as electrical and electronic parts such as switches, plugs andsockets and components for utility vehicles, particularly for the carsector. The compositions according to the invention are also suitablefor the production of the following shaped articles or moulded parts:interior fittings for rail vehicles, ships, aircraft, buses and othermotor vehicles, body parts for motor vehicles, housings for electricalappliances containing small transformers, housings for equipment fordata processing and transfer, housings and claddings for medicalequipment, massage equipment and housings therefor, toy vehicles forchildren, flat wall elements, housings for safety devices, thermallyinsulated transport containers, moldings for sanitary and bathequipment, covering grid plates for ventilation openings and housingsfor garden equipment.

EXAMPLES

Component A:

Linear polycarbonate based on bisphenol A with a weight-averagemolecular weight M_(w) of 28 000 g/mole (determined by GPC).

Component B-1:

SAN copolymer with an acrylonitrile content of 23 wt. % and aweight-average molecular weight of about 130 000 g/mole.

Component B-2:

ABS polymer with an acrylonitrile content:butadiene:styrene ratio of20:28:52 wt. %, produced by emulsion polymerization.

Component C-1:

Chopped glass strands with an average diameter of 13 μm and a size madeof epoxy resin produced from epichlorohydrin and bisphenol A. The carboncontent of component C-1 is 0.6 wt. %.

Component C-2:

Chopped glass strands with an average diameter of 13 μm and apolyurethane size. The carbon content of component C-1 is 0.4 wt. %.

Component D:

Metablen® SRK200 (Mitsubishi Rayon, Japan): styrene-acrylonitrilegrafted acrylate-silicone composite rubber, produced by emulsionpolymerization.

Component E-1: Pentaerythritol tetrastearate

Component E-2: Phosphite stabiliser

Production and Testing of the Molding Compositions According to theInvention

The components are mixed in a ZSK-25 twin screw extruder from Werner &Pfleiderer at a melt temperature of 260° C. The moldings are produced atmelt temperatures of 260° C. and 300° C. and a mould temperature of 80°C. using an injection molding machine of the Arburg 270 E type.

The melt viscosity measured at 260° C. and a shear rate of 1000 s⁻¹ inaccordance with ISO 11443 serves as a measure of the melt flowability.

The impact resistance is determined at 23° C. in accordance with ISO180-1U on specimens measuring 80 mm×10 mm×4 mm. The specimens wereinjection moulded at melt temperatures of 260° C. and 300° C. The changein impact resistance a_(k) on increasing the processing temperatureserves as a measure of the processing stability of the composition andis calculated as follows:

${{Processing}\mspace{14mu} {stability}} = {\frac{a_{K}^{260{^\circ}\mspace{14mu} {C.}} - a_{K}^{300{^\circ}\mspace{14mu} {C.}}}{a_{K}^{260{^\circ}\mspace{14mu} {C.}}}*100\%}$

The modulus of elasticity is determined on test bars injection mouldedat 260° C., in accordance with ISO 527.

The stress cracking (ES C) resistance in rapeseed oil at roomtemperature serves as a measure of the chemical resistance. The timetaken to fracture failure induced by stress cracking is determined on aspecimen measuring 80 mm×10 mm×4 mm, injection moulded at a melttemperature of 260° C., which is subjected to an outer fiber strain of2.4% using a strain jig and completely immersed in the medium. Themeasurement is performed on the basis of ISO 4599.

The reduction in impact resistance determined at 23° C. in accordancewith ISO 180-1U on specimens measuring 80 mm×10 mm×4 mm, injectionmoulded at 260° C., when stored in hot air at 120° C. for 1500 h servesas a measure of heat aging resistance.

The change in colour (change in grey scale) of specimens measuring 60mm×40 mm×2 mm, injection moulded at 260° C., subjected to hot lightaging in accordance with VW standard PV 1303 over 6 illumination cycles,serves as a measure of UV light resistance.

TABLE 1 Molding compositions and their properties 1 2 3 5 6 7 9 (cp.)(cp.) (cp.) 4 (cp.) (cp.) (cp.) 8 (cp.) 10 11 12 Components [parts bywt.] A PC 60.64 60.64 60.64 60.64 49.75 49.75 49.75 49.75 61.81 61.9449.46 43.52 B-1 SAN — 28.83 — 28.83 — 29.85 — 29.85 21.93 26.97 29.6725.72 B-2 ABS 28.83 — 28.83 — 29.85 — 29.85 — — — — — C-1 GF(epoxy-sized) — — 9.94 9.94 — — 19.90 19.90 9.97 9.99 19.78 29.67 C-2 GF(PU-sized) 9.94 9.94 — — 19.90 19.90 — — — — — — D Metablen SRK200 — — —— — — — — 5.98 0.50 0.49 0.49 E-1 PETS 0.50 0.50 0.50 0.50 0.40 0.400.40 0.40 0.20 0.50 0.49 0.49 E-2 Irganox B900 0.10 0.10 0.10 0.10 0.100.10 0.10 0.10 0.10 0.10 0.10 0.10 Properties Impact resistance a_(K)^(260° C.) 30 25 43 39 23 27 n.t. 40 39 37 40 38 [kJ/m²] Impactresistance a_(K) ^(300° C.) 33 17 n.t. 35 n.t. n.t. n.t. n.t. 39 37 3738 [kJ/m²] Processing stability [%] −10.0 32.0 n.t. 10.3 n.t. n.t. n.t.n.t. 0.0 0.0 7.5 0.0 Melt viscosity [Pas] 315 193 329 229 333 187 356202 247 212 198 233 Modulus of elasticity [MPa] 3736 5147 3961 5070 57297000 5994 7488 4623 5189 7604 10178 ESC-time to fracture [h] 1.5 0.1n.t. 21 0.5 0.02 n.t. 19 2.5 11 8 0.07 Change in toughness with heatn.t. n.t. n.t. n.t. −41 n.t. n.t. +4 n.t. n.t. n.t. n.t. aging (1500 hat 120° C.) [%] Colour change with hot light n.t. n.t. n.t. V −1.5 n.t.V +/−0 n.t. n.t. n.t. n.t. aging (change in grey scale in 6 cycles) n.t.= not tested

It can be seen from Table 1 that those compositions containing butadienerubber-modified styrene resin (comparative examples 1, 3, 5, 7 and 9) orSAN in combination with a relatively large amount of a rubber-modifiedgraft polymer (comparative example 9) exhibit inadequate flowability andan inadequate modulus of elasticity compared with examples according tothe invention having the same glass fiber content (examples 4, 8,10-12). Moreover, when butadiene rubber-modified styrene resins are used(comparative examples 5), the heat aging and light resistance are alsounsatisfactory. The compositions that do not contain glass fibers havingan epoxy polymer-based size (comparative examples 1, 2, 5 and 6) aredistinguished by poorer toughness compared with those comparablecompositions with glass fibers having an epoxy polymer-based size.Although the rubber-free compositions containing glass fibers without anepoxy polymer-based size (comparative examples 2 and 6) do exhibit goodflowability, they have very poor chemical resistance and processingstability. A good combination of flowability, rigidity, chemicalresistance, toughness, processing stability and aging resistance underthe effects of light and heat is only achieved in the compositionsaccording to the invention (examples 4, 8, 10-12).

Although the invention has been described in detail in the foregoing forthe purpose of illustration, it is to be understood that such detail issolely for that purpose and that variations may be made therein by thoseskilled in the art without departing from the spirit and scope of theinvention except as it may be limited by the claims.

Additional advantages, features and modifications will readily occur tothose skilled in the art. Therefore, the invention in its broaderaspects is not limited to the specific details, and representativedevices, shown and described herein. Accordingly, various modificationsmay be made without departing from the spirit or scope of the generalinventive concept as defined by the appended claims and theirequivalents.

All documents referred to herein are specifically incorporated herein byreference in their entireties.

As used herein and in the following claims, articles such as “the”, “a”and “an” can connote the singular or plural.

1. A composition comprising A) 10 to 85 parts by weight a polycarbonate,and/or a polyester carbonate, B) 10 to 50 parts by weight rubber-freevinyl copolymer, C) 5 to 50 parts by weight of sized glass fiber,wherein the size comprises an epoxy polymer, D) 0 to 2 parts by weightof a rubber-modified graft polymer, and E) 0 to 10 parts by weight of apolymer additive, the composition being free from rubber-modifiedpolymers which differ from component D).
 2. A composition according toclaim 1, comprising 15 to 40 parts by weight of said rubber-free vinylcopolymer.
 3. A composition according to claim 1, comprising 20 to 35parts by weight of rubber-free vinyl copolymer.
 4. A compositionaccording to claim 1, comprising 0 to 1 parts by weight of arubber-modified graft polymer.
 5. A composition according to claim 1,which is free from rubber-modified graft polymer.
 6. The compositionaccording to claim 1, wherein component C is a sized glass fiber withC.1 a glass fiber comprising at least one component selected from thegroup consisting of continuous strands, long glass fibers and choppedglass strands, C.2 a size containing an epoxy polymer, and C.3optionally an adhesion promoter.
 7. A composition according to claim 6comprising as component C, a glass fiber with a size C.2 consistingessentially of: C.2.1 50 to 100 wt. %, based on the total weight of C.2,of an epoxy polymer, and C.2.2 0 to 50 wt. %, based on the total weightof C.2, of at least one polymer selected from the group consisting ofthe polyurethanes, polyolefins, acrylate-containing polymers,styrene-containing polymers and polyamides.
 8. A composition accordingto claim 7, wherein the epoxy polymer C.2.1 comprises an epoxy resinmade from C.2.1.1 epichlorohydrin and C.2.1.2 an alcohol, which has atleast two hydroxyl groups.
 9. A composition according to claim 8, inwhich bisphenol A is used as the alcohol C.2.1.2.
 10. A compositionaccording to claim 1, wherein the sized glass fiber according tocomponent C has a carbon content of 0.1 to 1 wt. %.
 11. A compositionaccording to claims 1, wherein the glass fiber according to component Chas an average diameter of 5 to 25 μm.
 12. A composition according toclaims 1, wherein component E comprises at least one additive selectedfrom the group consisting of flame retardants, anti-drip agents,lubricants and mold release agents, nucleating agents, antistaticagents, stabilisers, fillers, reinforcing materials other than componentC, dyes and pigments.
 13. A composition according to claim 1, whereincomponent B is a rubber-free vinyl copolymer of B.1 70 to 80 wt. %,based on the total weight of component B, of at least one monomerselected from the group consisting of the vinyl aromatics andring-substituted vinyl aromatics and B.2 20 to 30 wt. %, based on thetotal weight of component B, of at least one monomer selected from thegroup consisting of the vinyl cyanides, (meth)acrylic acid (C₁-C₈) alkylesters, unsaturated carboxylic acids and derivatives of unsaturatedcarboxylic acids.
 14. A composition according to claim 13, whereincomponent B.1 is styrene and component B.2 is acrylonitrile.
 15. Acomposition according to claim 1, comprising as component D, arubber-based graft polymer which is substantially free from doublebonds.
 16. A composition according to claim 15, comprising as componentD, a rubber-based graft polymer selected from the group consisting ofacrylate rubber, silicone rubber and silicone-acrylate composite rubber.17. A method for the production of a shaped article comprising employinga composition according to claim
 1. 18. A shaped article comprising acomposition according to claim 1.